X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;ds=sidebyside;f=kern%2Fsem.c;h=a26c65ce18a7b38f9915b07d5cb2a6f557d4664f;hb=1b38e2c9925d6ec7fc50b327fc46d490f20d7ee0;hp=2262cb081d8306693cc13036903c1d0a4f92f69f;hpb=e05dacc96872c22d234af216d0728e46e8e222e0;p=bertos.git

diff --git a/kern/sem.c b/kern/sem.c
old mode 100755
new mode 100644
index 2262cb08..a26c65ce
--- a/kern/sem.c
+++ b/kern/sem.c
@@ -1,9 +1,34 @@
-/*!
+/**
  * \file
  * <!--
- * Copyright 2001,2004 Develer S.r.l. (http://www.develer.com/)
- * Copyright 1999,2000,2001 Bernardo Innocenti <bernie@develer.com>
- * This file is part of DevLib - See devlib/README for information.
+ * This file is part of BeRTOS.
+ *
+ * Bertos is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2001, 2004 Develer S.r.l. (http://www.develer.com/)
+ * Copyright 1999, 2000, 2001 Bernardo Innocenti <bernie@develer.com>
+ *
  * -->
  *
  * \brief Semaphore based synchronization services.
@@ -15,6 +40,27 @@
 
 /*#*
  *#* $Log$
+ *#* Revision 1.12  2006/07/19 12:56:27  bernie
+ *#* Convert to new Doxygen style.
+ *#*
+ *#* Revision 1.11  2006/02/24 01:17:05  bernie
+ *#* Update for new emulator.
+ *#*
+ *#* Revision 1.10  2005/11/04 16:20:02  bernie
+ *#* Fix reference to README.devlib in header.
+ *#*
+ *#* Revision 1.9  2005/04/11 19:10:28  bernie
+ *#* Include top-level headers from cfg/ subdir.
+ *#*
+ *#* Revision 1.8  2005/01/22 04:20:42  bernie
+ *#* Add integrity checks.
+ *#*
+ *#* Revision 1.7  2004/11/28 23:20:25  bernie
+ *#* Remove obsolete INITLIST macro.
+ *#*
+ *#* Revision 1.6  2004/10/21 10:57:21  bernie
+ *#* Use proc_forbid()/proc_permit().
+ *#*
  *#* Revision 1.5  2004/10/21 10:48:57  bernie
  *#* sem_release(): Simplify (made by rasky on scfirm).
  *#*
@@ -29,28 +75,34 @@
  *#*
  *#* Revision 1.1  2004/05/23 17:27:00  bernie
  *#* Import kern/ subdirectory.
- *#*
  *#*/
 
 #include "sem.h"
-#include "proc.h"
-#include "proc_p.h"
-#include "signal.h"
-#include "hw.h"
+#include <kern/proc.h>
+#include <kern/proc_p.h>
+#include <kern/signal.h>
+#include <cfg/debug.h>
+
+INLINE void sem_verify(struct Semaphore *s)
+{
+	LIST_ASSERT_VALID(&s->wait_queue);
+	ASSERT(s->nest_count >= 0);
+	ASSERT(s->nest_count < 128);   // heuristic max
+}
 
 
-/*!
- * \brief Initialize a Semaphore structure
+/**
+ * \brief Initialize a Semaphore structure.
  */
 void sem_init(struct Semaphore *s)
 {
-	INITLIST(&s->wait_queue);
+	LIST_INIT(&s->wait_queue);
 	s->owner = NULL;
 	s->nest_count = 0;
 }
 
 
-/*!
+/**
  * \brief Attempt to lock a semaphore without waiting.
  *
  * \return true in case of success, false if the semaphore
@@ -63,23 +115,23 @@ void sem_init(struct Semaphore *s)
  */
 bool sem_attempt(struct Semaphore *s)
 {
-	cpuflags_t flags;
-	DISABLE_IRQSAVE(flags);
+	bool result = false;
 
+	proc_forbid();
+	sem_verify(s);
 	if ((!s->owner) || (s->owner == CurrentProcess))
 	{
 		s->owner = CurrentProcess;
 		s->nest_count++;
-		ENABLE_INTS;
-		return true;
+		result = true;
 	}
+	proc_permit();
 
-	ENABLE_IRQRESTORE(flags);
-	return false;
+	return result;
 }
 
 
-/*!
+/**
  * \brief Lock a semaphore.
  *
  * If the semaphore is already owned by another process, the caller
@@ -98,35 +150,37 @@ bool sem_attempt(struct Semaphore *s)
  */
 void sem_obtain(struct Semaphore *s)
 {
-	cpuflags_t flags;
-	DISABLE_IRQSAVE(flags);
+	proc_forbid();
+	sem_verify(s);
 
 	/* Is the semaphore already locked by another process? */
 	if (UNLIKELY(s->owner && (s->owner != CurrentProcess)))
 	{
 		/* Append calling process to the wait queue */
 		ADDTAIL(&s->wait_queue, (Node *)CurrentProcess);
-		ENABLE_IRQRESTORE(flags);
 
 		/*
 		 * We will wake up only when the current owner calls
 		 * sem_release(). Then, the semaphore will already
 		 * be locked for us.
 		 */
+		proc_permit();
 		proc_schedule();
 	}
 	else
 	{
+		ASSERT(LIST_EMPTY(&s->wait_queue));
+
 		/* The semaphore was free: lock it */
 		s->owner = CurrentProcess;
 		s->nest_count++;
-		ENABLE_IRQRESTORE(flags);
+		proc_permit();
 	}
 }
 
 
-/*!
- * \brief Releases a lock on a previously locked semaphore.
+/**
+ * \brief Release a lock on a previously locked semaphore.
  *
  * If the nesting count of the semaphore reaches zero,
  * the next process waiting for it will be awaken.
@@ -140,12 +194,14 @@ void sem_obtain(struct Semaphore *s)
  */
 void sem_release(struct Semaphore *s)
 {
-	cpuflags_t flags;
-	DISABLE_IRQSAVE(flags);
+	proc_forbid();
+	sem_verify(s);
+
+	ASSERT(s->owner == CurrentProcess);
 
 	/*
 	 * Decrement nesting count and check if the semaphore
-	 * has been fully unlocked
+	 * has been fully unlocked.
 	 */
 	if (--s->nest_count == 0)
 	{
@@ -155,7 +211,7 @@ void sem_release(struct Semaphore *s)
 		s->owner = NULL;
 
 		/* Give semaphore to the first applicant, if any */
-		if ((proc = (Process*)REMHEAD(&s->wait_queue)))
+		if (UNLIKELY((proc = (Process *)list_remHead(&s->wait_queue))))
 		{
 			s->nest_count = 1;
 			s->owner = proc;
@@ -163,6 +219,5 @@ void sem_release(struct Semaphore *s)
 		}
 	}
 
-	ENABLE_IRQRESTORE(flags);
+	proc_permit();
 }
-